Chapter 2-3

Question 0

What is the definition and formula for speed? What is the common unit for speed?

Answer 0

Change in position with respect to time. Speed=d/t

S

Question 1

What are two fundamental components of motion?

Answer 1

Change in position and change in time

Question 2

What is velocity? How is it different from speed? Draw a vector and explain what it is.

Answer 2

How fast it is going plus direction.

30m
——>
Shows what direction it is going and how far.

Question 3

What is acceleration? What is the formula and common unit?

Answer 3

Rate at which motion changes over time.
M/s squared
A=vf-vi/t

Question 4

What is force? Force is represented by the use of vectors, draw two vectors and describe the net force.

Answer 4

A push or pull capable of changing an objects state in motion.
50
———–>

15
<——

The net force is 30N because you subtract the forces .

Question 5

Write the 4 fundamental forces from weakest to strongest.

Answer 5

Gravitational
Electromagnetic
Weak nuclear force
Strong nuclear force

Question 6

What is inertia?

Answer 6

Every object retains its state of rest of uniform straight-line motion unless acted upon by an unbalanced force.
Inertia resists any changes in motion
NEWTONS 1ST LAW
————————–

Question 7

Describe what free fall is? What is acceleration due to gravity, what two vertical formulas do you know?

Answer 7

Free fall is falling under influence of gravity without air resistance.

Speed of a falling object- gravity x time. V=gt
Distance of a free falling object- d=1/2gt(squared)

Question 8

Describe compound motion and explain what it is through projectile motion.

If you throw an object straight up, describe what happens to acceleration on the way up, at the top, and down.

Answer 8

Compound motion is an object thrown into the air. Yah tough projectile motion the object is thrown vertically in the air slowing as it comes to the top and accelerating coming down to the ground.

Question 9

Write newtons three laws in your own words

Answer 9

Newtons 1st law: any object in motion stays in motion unless being acted upon.

Newtons 2nd law: more mass less speed, less mass more speed.

Newtons 3rd law: every force there’s an equal and opposite reaction

Question 10

What is momentum, what is the formula?

Answer 10

Includes both effects of motion and inertia.

P=mv
Momentum=mass x velocity

Question 11

Explain how momentum and energy is conserved

Answer 11

The total momentum of a group of interacting objects remains the same in the absence of external forces.

Question 12

What is impulse? Explain how increasing the contact time decreases the force applied.
Give real life examples.

Answer 12

A force acting on an object for some time, an impulse produces a change in momentum.

Getting in a car accident and the air bag goes off, the longer your face is in contact with the air bag the less the force is applied.

Question 13

What is centripetal acceleration and centripetal force?

Answer 13

Centripetal acceleration is present, centripetal force must be acting.

Like a washer machine or a centrifuge.

Question 14

Explain centrifugal force and give it real life examples

Answer 14

Centrifugal force is the apparent outward tug as direction changes

The ride at the state fair dealing with gravity that spins around really fast and you get sucked to the side and start sliding upwards.

Question 15

Explain newtons law of gravitation. Why are we not being pulled together due to the force of gravity?

Answer 15

It’s the attractive force between all masses. We don’t feel the gravity between each other and other objects because the earth is so big and we are so small,

That every object in the universe is attracted to every other object in the universe.

Question 16

Describe how an object can have more potential energy and kinetic energy?

Answer 16

By changing the position and the energy associated with the motion.

Question 17

State the 7 major energy sources used today. Give an example of each and know which are the most common and least common, rank in order.

Answer 17

1

  Petroleum-non renewable-oil from oil, bearing rock, fracking #2
   Coal- non renewable- fossil fuels #3 
   Moving water-#1in renewable-rivers #4 
   Nuclear-non renewable- reactions based off of uranium and plutonium #5
   Modern solar technologies-#2 in renewable-wind towers #6
   Geothermal- renewable-on the rise- below earths surface, dry steam #7
   Hydrogen-least common in renewable.- used only in fuel cell or burned to release heat, only emission is water, must be obtained from chemical reaction.

Question 18

At six flags great adventure amusement park in New Jersey, a popular ride known as “free fall” carries passengers up to a height of 33.5m and drops them to the ground inside a small cage. How fast are the passengers going at the bottom of this exhilarating journey?

Answer 18

33.5m

33. 5=4.9t(squared)
    - — ——
34. 9 4.9

68 x 36 t(squared) = 8.6s

Question 19

How far can a mother push a baby carriage if she can do 2920j of work and the carriage has a mass of 20.0kg

Answer 19

2920J
20.0kg

20x9.8=196

2920=196xd

196. 196. D= 14.9m

Question 20

You carry a 20.0N bag of dog food up a 6.00M flight of stairs. How much work was done

Answer 20

W=fxd

20 x 6.00= 120J